This microcomputer (PDP 11/03) data system supervises the acquisition and processing of information from an analytical ultracentrifuge and a circular dichromic spectropolarimeter used in MDB, NHLBI, to investigate the interactions betweenhuman lipoprotein subunits. Current capabilities inlude acquisition, display, and preprocessing of data from the ultracentrifuge and transfer of preprocessed data files to the DECsystem-10 for further analysis under MLAB using predefined procedures invoked by a few simple commands. Software support for the spectropolarimeter includes the ability to add, subtract and average CD spectra and to transfer files to the PDP-10 for further analysis. The results of a study of system performance with very dilute solutions were presented at the 1982 FASEB meeting in New Orleans. Plans are now underway for modification of the ultracentrifuge interface to provide greater noise immunity and for the addition of a digital plotter to the system.